#include<stdio.h>
#include<string.h>

int main(int argc, char* argv[]){
  if(argc != 2){
    printf("Usage: %s [-a | -b | -c]\n",argv[0]);
  }
  const char* arg = argv[1];
  if(strcmp(arg,"-a") == 0) 
    printf("这是功能1\n");
  else if(strcmp(arg,"-b") == 0)
    printf("这是功能2\n");
  else if(strcmp(arg, "-c") == 0)
    printf("这是功能3\n");
 // for(int i = 0; i < argc; i++){
 //   printf("argv[%d]: %s\n", i, argv[i]);
 // }
  return 0;
}
